<?PHP  // $Id$
/**
 * assignment_base is the base class for assignment types
 *
 * This class provides all the functionality for an assignment
 */

DEFINE ('ASSIGNMENT_COUNT_WORDS', 1);
DEFINE ('ASSIGNMENT_COUNT_LETTERS', 2);

/**
 * Standard base class for all assignment submodules (assignment types).
 */
class assignment_base {

	var $cm;
	var $course;
	var $assignment;
	var $strassignment;
	var $strassignments;
	var $strsubmissions;
	var $strlastmodified;
	var $pagetitle;
	var $usehtmleditor;
	var $defaultformat;
	var $context;
	var $type;

	/**
	 * Constructor for the base assignment class
	 *
	 * Constructor for the base assignment class.
	 * If cmid is set create the cm, course, assignment objects.
	 * If the assignment is hidden and the user is not a teacher then
	 * this prints a page header and notice.
	 *
	 * @param cmid   integer, the current course module id - not set for new assignments
	 * @param assignment   object, usually null, but if we have it we pass it to save db access
	 * @param cm   object, usually null, but if we have it we pass it to save db access
	 * @param course   object, usually null, but if we have it we pass it to save db access
	 */
	function assignment_base($cmid='staticonly', $assignment=NULL, $cm=NULL, $course=NULL) {
		global $COURSE;

		if ($cmid == 'staticonly') {
			//use static functions only!
			return;
		}

		global $CFG;

		if ($cm) {
			$this->cm = $cm;
		} else if (! $this->cm = get_coursemodule_from_id('assignment', $cmid)) {
			error('Course Module ID was incorrect');
		}

		$this->context = get_context_instance(CONTEXT_MODULE, $this->cm->id);

		if ($course) {
			$this->course = $course;
		} else if ($this->cm->course == $COURSE->id) {
			$this->course = $COURSE;
		} else if (! $this->course = get_record('course', 'id', $this->cm->course)) {
			error('Course is misconfigured');
		}

		if ($assignment) {
			$this->assignment = $assignment;
		} else if (! $this->assignment = get_record('assignment', 'id', $this->cm->instance)) {
			error('assignment ID was incorrect');
		}

		$this->assignment->cmidnumber = $this->cm->id;	 // compatibility with modedit assignment obj
		$this->assignment->courseid   = $this->course->id; // compatibility with modedit assignment obj

		$this->strassignment = get_string('modulename', 'assignment');
		$this->strassignments = get_string('modulenameplural', 'assignment');
		$this->strsubmissions = get_string('submissions', 'assignment');
		$this->strlastmodified = get_string('lastmodified');
		$this->pagetitle = strip_tags($this->course->shortname.': '.$this->strassignment.': '.format_string($this->assignment->name,true));

		// visibility handled by require_login() with $cm parameter
		// get current group only when really needed

	/// Set up things for a HTML editor if it's needed
		if ($this->usehtmleditor = can_use_html_editor()) {
			$this->defaultformat = FORMAT_HTML;
		} else {
			$this->defaultformat = FORMAT_MOODLE;
		}
	}

	/**
	 * Display the assignment, used by view.php
	 *
	 * This in turn calls the methods producing individual parts of the page
	 */
	function view() {

		$context = get_context_instance(CONTEXT_MODULE,$this->cm->id);
		require_capability('mod/assignment:view', $context);

		add_to_log($this->course->id, "assignment", "view", "view.php?id={$this->cm->id}",
				   $this->assignment->id, $this->cm->id);

		$this->view_header();

		$this->view_intro();

		$this->view_dates();

		$this->view_feedback();

		$this->view_footer();
	}

	/**
	 * Display the header and top of a page
	 *
	 * (this doesn't change much for assignment types)
	 * This is used by the view() method to print the header of view.php but
	 * it can be used on other pages in which case the string to denote the
	 * page in the navigation trail should be passed as an argument
	 *
	 * @param $subpage string Description of subpage to be used in navigation trail
	 */
	function view_header($subpage='') {

		global $CFG;


		if ($subpage) {
			$navigation = build_navigation($subpage, $this->cm);
		} else {
			$navigation = build_navigation('', $this->cm);
		}

		print_header($this->pagetitle, $this->course->fullname, $navigation, '', '',
					 true, update_module_button($this->cm->id, $this->course->id, $this->strassignment),
					 navmenu($this->course, $this->cm));

		groups_print_activity_menu($this->cm, 'view.php?id=' . $this->cm->id);

		echo '<div class="reportlink">'.$this->submittedlink().'</div>';
		echo '<div class="clearer"></div>';
	}


	/**
	 * Display the assignment intro
	 *
	 * This will most likely be extended by assignment type plug-ins
	 * The default implementation prints the assignment description in a box
	 */
	function view_intro() {
		print_simple_box_start('center', '', '', 0, 'generalbox', 'intro');
		$formatoptions = new stdClass;
		$formatoptions->noclean = true;
		echo format_text($this->assignment->description, $this->assignment->format, $formatoptions);
		print_simple_box_end();
	}

	/**
	 * Display the assignment dates
	 *
	 * Prints the assignment start and end dates in a box.
	 * This will be suitable for most assignment types
	 */
	function view_dates() {
		if (!$this->assignment->timeavailable && !$this->assignment->timedue) {
			return;
		}

		print_simple_box_start('center', '', '', 0, 'generalbox', 'dates');
		echo '<table>';
		if ($this->assignment->timeavailable) {
			echo '<tr><td class="c0">'.get_string('availabledate','assignment').':</td>';
			echo '	<td class="c1">'.userdate($this->assignment->timeavailable).'</td></tr>';
		}
		if ($this->assignment->timedue) {
			echo '<tr><td class="c0">'.get_string('duedate','assignment').':</td>';
			echo '	<td class="c1">'.userdate($this->assignment->timedue).'</td></tr>';
		}
		echo '</table>';
		print_simple_box_end();
	}


	/**
	 * Display the bottom and footer of a page
	 *
	 * This default method just prints the footer.
	 * This will be suitable for most assignment types
	 */
	function view_footer() {
		print_footer($this->course);
	}

	/**
	 * Display the feedback to the student
	 *
	 * This default method prints the teacher picture and name, date when marked,
	 * grade and teacher submissioncomment.
	 *
	 * @param $submission object The submission object or NULL in which case it will be loaded
	 */
	function view_feedback($submission=NULL) {
		global $USER, $CFG;
		require_once($CFG->libdir.'/gradelib.php');

		if (!has_capability('mod/assignment:submit', $this->context, $USER->id, false)) {
			// can not submit assignments -> no feedback
			return;
		}

		if (!$submission) { /// Get submission for this assignment
			$submission = $this->get_submission($USER->id);
		}

		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, $USER->id);
		$item = $grading_info->items[0];
		$grade = $item->grades[$USER->id];

		if ($grade->hidden or $grade->grade === false) { // hidden or error
			return;
		}

		if ($grade->grade === null and empty($grade->str_feedback)) {   /// Nothing to show yet
			return;
		}

		$graded_date = $grade->dategraded;
		$graded_by   = $grade->usermodified;

	/// We need the teacher info
		if (!$teacher = get_record('user', 'id', $graded_by)) {
			error('Could not find the teacher');
		}

	/// Print the feedback
		print_heading(get_string('feedbackfromteacher', 'assignment', $this->course->teacher)); // TODO: fix teacher string

		echo '<table cellspacing="0" class="feedback">';

		echo '<tr>';
		echo '<td class="left picture">';
		if ($teacher) {
			print_user_picture($teacher, $this->course->id, $teacher->picture);
		}
		echo '</td>';
		echo '<td class="topic">';
		echo '<div class="from">';
		if ($teacher) {
			echo '<div class="fullname">'.fullname($teacher).'</div>';
		}
		echo '<div class="time">'.userdate($graded_date).'</div>';
		echo '</div>';
		echo '</td>';
		echo '</tr>';

		echo '<tr>';
		echo '<td class="left side">&nbsp;</td>';
		echo '<td class="content">';
		echo '<div class="grade">';
		echo get_string("grade").': '.$grade->str_long_grade;
		echo '</div>';
		echo '<div class="clearer"></div>';

		echo '<div class="comment">';
		echo $grade->str_feedback;
		echo '</div>';
		echo '</tr>';

		echo '</table>';
	}

	/**
	 * Returns a link with info about the state of the assignment submissions
	 *
	 * This is used by view_header to put this link at the top right of the page.
	 * For teachers it gives the number of submitted assignments with a link
	 * For students it gives the time of their submission.
	 * This will be suitable for most assignment types.
	 * @param bool $allgroup print all groups info if user can access all groups, suitable for index.php
	 * @return string
	 */
	function submittedlink($allgroups=false) {
		global $USER;

		$submitted = '';

		$context = get_context_instance(CONTEXT_MODULE,$this->cm->id);
		if (has_capability('mod/assignment:grade', $context)) {
			if ($allgroups and has_capability('moodle/site:accessallgroups', $context)) {
				$group = 0;
			} else {
				$group = groups_get_activity_group($this->cm);
			}
			if ($count = $this->count_real_submissions($group)) {
				$submitted = '<a href="submissions.php?id='.$this->cm->id.'">'.
							 get_string('viewsubmissions', 'assignment', $count).'</a>';
			} else {
				$submitted = '<a href="submissions.php?id='.$this->cm->id.'">'.
							 get_string('noattempts', 'assignment').'</a>';
			}
		} else {
			if (!empty($USER->id)) {
				if ($submission = $this->get_submission($USER->id)) {
					if ($submission->timemodified) {
						if ($submission->timemodified <= $this->assignment->timedue || empty($this->assignment->timedue)) {
							$submitted = '<span class="early">'.userdate($submission->timemodified).'</span>';
						} else {
							$submitted = '<span class="late">'.userdate($submission->timemodified).'</span>';
						}
					}
				}
			}
		}

		return $submitted;
	}


	function setup_elements(&$mform) {

	}

	/**
	 * Create a new assignment activity
	 *
	 * Given an object containing all the necessary data,
	 * (defined by the form in mod.html) this function
	 * will create a new instance and return the id number
	 * of the new instance.
	 * The due data is added to the calendar
	 * This is common to all assignment types.
	 *
	 * @param $assignment object The data from the form on mod.html
	 * @return int The id of the assignment
	 */
	function add_instance($assignment) {
		global $COURSE;

		$assignment->timemodified = time();
		$assignment->courseid = $assignment->course;

		if ($returnid = insert_record("assignment", $assignment)) {
			$assignment->id = $returnid;

			if ($assignment->timedue) {
				$event = new object();
				$event->name		= $assignment->name;
				$event->description = $assignment->description;
				$event->courseid	= $assignment->course;
				$event->groupid	 = 0;
				$event->userid	  = 0;
				$event->modulename  = 'assignment';
				$event->instance	= $returnid;
				$event->eventtype   = 'due';
				$event->timestart   = $assignment->timedue;
				$event->timeduration = 0;

				add_event($event);
			}

			$assignment = stripslashes_recursive($assignment);
			assignment_grade_item_update($assignment);

		}


		return $returnid;
	}

	/**
	 * Deletes an assignment activity
	 *
	 * Deletes all database records, files and calendar events for this assignment.
	 * @param $assignment object The assignment to be deleted
	 * @return boolean False indicates error
	 */
	function delete_instance($assignment) {
		global $CFG;

		$assignment->courseid = $assignment->course;

		$result = true;

		if (! delete_records('assignment_submissions', 'assignment', $assignment->id)) {
			$result = false;
		}

		if (! delete_records('assignment', 'id', $assignment->id)) {
			$result = false;
		}

		if (! delete_records('event', 'modulename', 'assignment', 'instance', $assignment->id)) {
			$result = false;
		}

		// delete file area with all attachments - ignore errors
		require_once($CFG->libdir.'/filelib.php');
		fulldelete($CFG->dataroot.'/'.$assignment->course.'/'.$CFG->moddata.'/assignment/'.$assignment->id);

		assignment_grade_item_delete($assignment);

		return $result;
	}

	/**
	 * Updates a new assignment activity
	 *
	 * Given an object containing all the necessary data,
	 * (defined by the form in mod.html) this function
	 * will update the assignment instance and return the id number
	 * The due date is updated in the calendar
	 * This is common to all assignment types.
	 *
	 * @param $assignment object The data from the form on mod.html
	 * @return int The assignment id
	 */
	function update_instance($assignment) {
		global $COURSE;

		$assignment->timemodified = time();

		$assignment->id = $assignment->instance;
		$assignment->courseid = $assignment->course;

		if (!update_record('assignment', $assignment)) {
			return false;
		}

		if ($assignment->timedue) {
			$event = new object();

			if ($event->id = get_field('event', 'id', 'modulename', 'assignment', 'instance', $assignment->id)) {

				$event->name		= $assignment->name;
				$event->description = $assignment->description;
				$event->timestart   = $assignment->timedue;

				update_event($event);
			} else {
				$event = new object();
				$event->name		= $assignment->name;
				$event->description = $assignment->description;
				$event->courseid	= $assignment->course;
				$event->groupid	 = 0;
				$event->userid	  = 0;
				$event->modulename  = 'assignment';
				$event->instance	= $assignment->id;
				$event->eventtype   = 'due';
				$event->timestart   = $assignment->timedue;
				$event->timeduration = 0;

				add_event($event);
			}
		} else {
			delete_records('event', 'modulename', 'assignment', 'instance', $assignment->id);
		}

		// get existing grade item
		$assignment = stripslashes_recursive($assignment);

		assignment_grade_item_update($assignment);

		return true;
	}

	/**
	 * Update grade item for this submission.
	 */
	function update_grade($submission) {
		assignment_update_grades($this->assignment, $submission->userid);
	}

	/**
	 * Top-level function for handling of submissions called by submissions.php
	 *
	 * This is for handling the teacher interaction with the grading interface
	 * This should be suitable for most assignment types.
	 *
	 * @param $mode string Specifies the kind of teacher interaction taking place
	 */
	function submissions($mode) {
		///The main switch is changed to facilitate
		///1) Batch fast grading
		///2) Skip to the next one on the popup
		///3) Save and Skip to the next one on the popup

		//make user global so we can use the id
		global $USER;

		$mailinfo = optional_param('mailinfo', null, PARAM_BOOL);
		if (is_null($mailinfo)) {
			$mailinfo = get_user_preferences('assignment_mailinfo', 0);
		} else {
			set_user_preference('assignment_mailinfo', $mailinfo);
		}

		switch ($mode) {
			case 'grade':						 // We are in a popup window grading
				if ($submission = $this->process_feedback()) {
					//IE needs proper header with encoding
					print_header(get_string('feedback', 'assignment').':'.format_string($this->assignment->name));
					print_heading(get_string('changessaved'));
					print $this->update_main_listing($submission);
				}
				close_window();
				break;

			case 'single':						// We are in a popup window displaying submission
				$this->display_submission();
				break;

			case 'all':						  // Main window, display everything
				$this->display_submissions();
				break;

			case 'fastgrade':
				///do the fast grading stuff  - this process should work for all 3 subclasses

				$grading	= false;
				$commenting = false;
				$col		= false;
				if (isset($_POST['submissioncomment'])) {
					$col = 'submissioncomment';
					$commenting = true;
				}
				if (isset($_POST['menu'])) {
					$col = 'menu';
					$grading = true;
				}
				if (!$col) {
					//both submissioncomment and grade columns collapsed..
					$this->display_submissions();
					break;
				}

				foreach ($_POST[$col] as $id => $unusedvalue){

					$id = (int)$id; //clean parameter name

					$this->process_outcomes($id);

					if (!$submission = $this->get_submission($id)) {
						$submission = $this->prepare_new_submission($id);
						$newsubmission = true;
					} else {
						$newsubmission = false;
					}
					unset($submission->data1);  // Don't need to update this.
					unset($submission->data2);  // Don't need to update this.

					//for fast grade, we need to check if any changes take place
					$updatedb = false;

					if ($grading) {
						$grade = $_POST['menu'][$id];
						$updatedb = $updatedb || ($submission->grade != $grade);
						$submission->grade = $grade;
					} else {
						if (!$newsubmission) {
							unset($submission->grade);  // Don't need to update this.
						}
					}
					if ($commenting) {
						$commentvalue = trim($_POST['submissioncomment'][$id]);
						$updatedb = $updatedb || ($submission->submissioncomment != stripslashes($commentvalue));
						$submission->submissioncomment = $commentvalue;
					} else {
						unset($submission->submissioncomment);  // Don't need to update this.
					}

					$submission->teacher	= $USER->id;
					if ($updatedb) {
						$submission->mailed = (int)(!$mailinfo);
					}

					$submission->timemarked = time();

					//if it is not an update, we don't change the last modified time etc.
					//this will also not write into database if no submissioncomment and grade is entered.

					if ($updatedb){
						if ($newsubmission) {
							if (!isset($submission->submissioncomment)) {
								$submission->submissioncomment = '';
							}
							if (!$sid = insert_record('assignment_submissions', $submission)) {
								return false;
							}
							$submission->id = $sid;
						} else {
							if (!update_record('assignment_submissions', $submission)) {
								return false;
							}
						}

						// triger grade event
						$this->update_grade($submission);

						//add to log only if updating
						add_to_log($this->course->id, 'assignment', 'update grades',
								   'submissions.php?id='.$this->assignment->id.'&user='.$submission->userid,
								   $submission->userid, $this->cm->id);
					}

				}

				$message = notify(get_string('changessaved'), 'notifysuccess', 'center', true);

				$this->display_submissions($message);
				break;


			case 'next':
				/// We are currently in pop up, but we want to skip to next one without saving.
				///	This turns out to be similar to a single case
				/// The URL used is for the next submission.

				$this->display_submission();
				break;

			case 'saveandnext':
				///We are in pop up. save the current one and go to the next one.
				//first we save the current changes
				if ($submission = $this->process_feedback()) {
					//print_heading(get_string('changessaved'));
					$extra_javascript = $this->update_main_listing($submission);
				}

				//then we display the next submission
				$this->display_submission($extra_javascript);
				break;

			default:
				echo "something seriously is wrong!!";
				break;
		}
	}

	/**
	* Helper method updating the listing on the main script from popup using javascript
	*
	* @param $submission object The submission whose data is to be updated on the main page
	*/
	function update_main_listing($submission) {
		global $SESSION, $CFG;

		$output = '';

		$perpage = get_user_preferences('assignment_perpage', 10);

		$quickgrade = get_user_preferences('assignment_quickgrade', 0);

		/// Run some Javascript to try and update the parent page
		$output .= '<script type="text/javascript">'."\n<!--\n";
		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['submissioncomment'])) {
			if ($quickgrade){
				$output.= 'opener.document.getElementById("submissioncomment'.$submission->userid.'").value="'
				.trim($submission->submissioncomment).'";'."\n";
			 } else {
				$output.= 'opener.document.getElementById("com'.$submission->userid.
				'").innerHTML="'.shorten_text(trim(strip_tags($submission->submissioncomment)), 15)."\";\n";
			}
		}

		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['grade'])) {
			//echo optional_param('menuindex');
			if ($quickgrade){
				$output.= 'opener.document.getElementById("menumenu'.$submission->userid.
				'").selectedIndex="'.optional_param('menuindex', 0, PARAM_INT).'";'."\n";
			} else {
				$output.= 'opener.document.getElementById("g'.$submission->userid.'").innerHTML="'.
				$this->display_grade($submission->grade)."\";\n";
			}
		}
		//need to add student's assignments in there too.
		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['timemodified']) &&
			$submission->timemodified) {
			$output.= 'opener.document.getElementById("ts'.$submission->userid.
				 '").innerHTML="'.addslashes_js($this->print_student_answer($submission->userid)).userdate($submission->timemodified)."\";\n";
		}

		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['timemarked']) &&
			$submission->timemarked) {
			$output.= 'opener.document.getElementById("tt'.$submission->userid.
				 '").innerHTML="'.userdate($submission->timemarked)."\";\n";
		}

		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['status'])) {
			$output.= 'opener.document.getElementById("up'.$submission->userid.'").className="s1";';
			$buttontext = get_string('update');
			$button = link_to_popup_window ('/mod/assignment/submissions.php?id='.$this->cm->id.'&amp;userid='.$submission->userid.'&amp;mode=single'.'&amp;offset='.(optional_param('offset', '', PARAM_INT)-1),
					  'grade'.$submission->userid, $buttontext, 450, 700, $buttontext, 'none', true, 'button'.$submission->userid);
			$output.= 'opener.document.getElementById("up'.$submission->userid.'").innerHTML="'.addslashes_js($button).'";';
		}

		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, $submission->userid);

		if (empty($SESSION->flextable['mod-assignment-submissions']->collapse['finalgrade'])) {
			$output.= 'opener.document.getElementById("finalgrade_'.$submission->userid.
			'").innerHTML="'.$grading_info->items[0]->grades[$submission->userid]->str_grade.'";'."\n";
		}

		if (!empty($CFG->enableoutcomes) and empty($SESSION->flextable['mod-assignment-submissions']->collapse['outcome'])) {

			if (!empty($grading_info->outcomes)) {
				foreach($grading_info->outcomes as $n=>$outcome) {
					if ($outcome->grades[$submission->userid]->locked) {
						continue;
					}

					if ($quickgrade){
						$output.= 'opener.document.getElementById("outcome_'.$n.'_'.$submission->userid.
						'").selectedIndex="'.$outcome->grades[$submission->userid]->grade.'";'."\n";

					} else {
						$options = make_grades_menu(-$outcome->scaleid);
						$options[0] = get_string('nooutcome', 'grades');
						$output.= 'opener.document.getElementById("outcome_'.$n.'_'.$submission->userid.'").innerHTML="'.$options[$outcome->grades[$submission->userid]->grade]."\";\n";
					}

				}
			}
		}

		$output .= "\n-->\n</script>";
		return $output;
	}

	/**
	 *  Return a grade in user-friendly form, whether it's a scale or not
	 *
	 * @param $grade
	 * @return string User-friendly representation of grade
	 */
	function display_grade($grade) {

		static $scalegrades = array();   // Cache scales for each assignment - they might have different scales!!

		if ($this->assignment->grade >= 0) {	// Normal number
			if ($grade == -1) {
				return '-';
			} else {
				return $grade.' / '.$this->assignment->grade;
			}

		} else {								// Scale
			if (empty($scalegrades[$this->assignment->id])) {
				if ($scale = get_record('scale', 'id', -($this->assignment->grade))) {
					$scalegrades[$this->assignment->id] = make_menu_from_list($scale->scale);
				} else {
					return '-';
				}
			}
			if (isset($scalegrades[$this->assignment->id][$grade])) {
				return $scalegrades[$this->assignment->id][$grade];
			}
			return '-';
		}
	}

	/**
	 *  Display a single submission, ready for grading on a popup window
	 *
	 * This default method prints the teacher info and submissioncomment box at the top and
	 * the student info and submission at the bottom.
	 * This method also fetches the necessary data in order to be able to
	 * provide a "Next submission" button.
	 * Calls preprocess_submission() to give assignment type plug-ins a chance
	 * to process submissions before they are graded
	 * This method gets its arguments from the page parameters userid and offset
	 */
	function display_submission($extra_javascript = '') {

		global $CFG;
		require_once($CFG->libdir.'/gradelib.php');
		require_once($CFG->libdir.'/tablelib.php');

		$userid = required_param('userid', PARAM_INT);
		$offset = required_param('offset', PARAM_INT);//offset for where to start looking for student.

		if (!$user = get_record('user', 'id', $userid)) {
			error('No such user!');
		}

		if (!$submission = $this->get_submission($user->id)) {
			$submission = $this->prepare_new_submission($userid);
		}
		if ($submission->timemodified > $submission->timemarked) {
			$subtype = 'assignmentnew';
		} else {
			$subtype = 'assignmentold';
		}

		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, array($user->id));
		$disabled = $grading_info->items[0]->grades[$userid]->locked || $grading_info->items[0]->grades[$userid]->overridden;

	/// construct SQL, using current offset to find the data of the next student
		$course	 = $this->course;
		$assignment = $this->assignment;
		$cm		 = $this->cm;
		$context	= get_context_instance(CONTEXT_MODULE, $cm->id);

		/// Get all ppl that can submit assignments

		$currentgroup = groups_get_activity_group($cm);
		if ($users = get_users_by_capability($context, 'mod/assignment:submit', 'u.id', '', '', '', $currentgroup, '', false)) {
			$users = array_keys($users);
		}

		// if groupmembersonly used, remove users who are not in any group
		if ($users and !empty($CFG->enablegroupings) and $cm->groupmembersonly) {
			if ($groupingusers = groups_get_grouping_members($cm->groupingid, 'u.id', 'u.id')) {
				$users = array_intersect($users, array_keys($groupingusers));
			}
		}

		$nextid = 0;

		if ($users) {
			$select = 'SELECT u.id, u.firstname, u.lastname, u.picture, u.imagealt,
							  s.id AS submissionid, s.grade, s.submissioncomment,
							  s.timemodified, s.timemarked,
							  COALESCE(SIGN(SIGN(s.timemarked) + SIGN(s.timemarked - s.timemodified)), 0) AS status ';
			$sql = 'FROM '.$CFG->prefix.'user u '.
				   'LEFT JOIN '.$CFG->prefix.'assignment_submissions s ON u.id = s.userid
																	  AND s.assignment = '.$this->assignment->id.' '.
				   'WHERE u.id IN ('.implode(',', $users).') ';

			if ($sort = flexible_table::get_sql_sort('mod-assignment-submissions')) {
				$sort = 'ORDER BY '.$sort.' ';
			}

			if (($auser = get_records_sql($select.$sql.$sort, $offset+1, 1)) !== false) {
				$nextuser = array_shift($auser);
			/// Calculate user status
				$nextuser->status = ($nextuser->timemarked > 0) && ($nextuser->timemarked >= $nextuser->timemodified);
				$nextid = $nextuser->id;
			}
		}

		print_header(get_string('feedback', 'assignment').':'.fullname($user, true).':'.format_string($this->assignment->name));

		/// Print any extra javascript needed for saveandnext
		echo $extra_javascript;

		///SOme javascript to help with setting up >.>

		echo '<script type="text/javascript">'."\n";
		echo 'function setNext(){'."\n";
		echo 'document.getElementById(\'submitform\').mode.value=\'next\';'."\n";
		echo 'document.getElementById(\'submitform\').userid.value="'.$nextid.'";'."\n";
		echo '}'."\n";

		echo 'function saveNext(){'."\n";
		echo 'document.getElementById(\'submitform\').mode.value=\'saveandnext\';'."\n";
		echo 'document.getElementById(\'submitform\').userid.value="'.$nextid.'";'."\n";
		echo 'document.getElementById(\'submitform\').saveuserid.value="'.$userid.'";'."\n";
		echo 'document.getElementById(\'submitform\').menuindex.value = document.getElementById(\'submitform\').grade.selectedIndex;'."\n";
		echo '}'."\n";

		echo '</script>'."\n";
		echo '<table cellspacing="0" class="feedback '.$subtype.'" >';

		///Start of teacher info row

		echo '<tr>';
		echo '<td class="picture teacher">';
		if ($submission->teacher) {
			$teacher = get_record('user', 'id', $submission->teacher);
		} else {
			global $USER;
			$teacher = $USER;
		}
		print_user_picture($teacher, $this->course->id, $teacher->picture);
		echo '</td>';
		echo '<td class="content">';
		echo '<form id="submitform" action="submissions.php" method="post">';
		echo '<div>'; // xhtml compatibility - invisiblefieldset was breaking layout here
		echo '<input type="hidden" name="offset" value="'.($offset+1).'" />';
		echo '<input type="hidden" name="userid" value="'.$userid.'" />';
		echo '<input type="hidden" name="id" value="'.$this->cm->id.'" />';
		echo '<input type="hidden" name="mode" value="grade" />';
		echo '<input type="hidden" name="menuindex" value="0" />';//selected menu index

		//new hidden field, initialized to -1.
		echo '<input type="hidden" name="saveuserid" value="-1" />';

		if ($submission->timemarked) {
			echo '<div class="from">';
			echo '<div class="fullname">'.fullname($teacher, true).'</div>';
			echo '<div class="time">'.userdate($submission->timemarked).'</div>';
			echo '</div>';
		}
		echo '<div class="grade"><label for="menugrade">'.get_string('grade').'</label> ';
		choose_from_menu(make_grades_menu($this->assignment->grade), 'grade', $submission->grade, get_string('nograde'), '', -1, false, $disabled);
		echo '</div>';

		echo '<div class="clearer"></div>';
		echo '<div class="finalgrade">'.get_string('finalgrade', 'grades').': '.$grading_info->items[0]->grades[$userid]->str_grade.'</div>';
		echo '<div class="clearer"></div>';

		if (!empty($CFG->enableoutcomes)) {
			foreach($grading_info->outcomes as $n=>$outcome) {
				echo '<div class="outcome"><label for="menuoutcome_'.$n.'">'.$outcome->name.'</label> ';
				$options = make_grades_menu(-$outcome->scaleid);
				if ($outcome->grades[$submission->userid]->locked) {
					$options[0] = get_string('nooutcome', 'grades');
					echo $options[$outcome->grades[$submission->userid]->grade];
				} else {
					choose_from_menu($options, 'outcome_'.$n.'['.$userid.']', $outcome->grades[$submission->userid]->grade, get_string('nooutcome', 'grades'), '', 0, false, false, 0, 'menuoutcome_'.$n);
				}
				echo '</div>';
				echo '<div class="clearer"></div>';
			}
		}


		$this->preprocess_submission($submission);

		if ($disabled) {
			echo '<div class="disabledfeedback">'.$grading_info->items[0]->grades[$userid]->str_feedback.'</div>';

		} else {
			print_textarea($this->usehtmleditor, 14, 58, 0, 0, 'submissioncomment', $submission->submissioncomment, $this->course->id);
			if ($this->usehtmleditor) {
				echo '<input type="hidden" name="format" value="'.FORMAT_HTML.'" />';
			} else {
				echo '<div class="format">';
				choose_from_menu(format_text_menu(), "format", $submission->format, "");
				helpbutton("textformat", get_string("helpformatting"));
				echo '</div>';
			}
		}

		$lastmailinfo = get_user_preferences('assignment_mailinfo', 1) ? 'checked="checked"' : '';

		///Print Buttons in Single View
		echo '<input type="hidden" name="mailinfo" value="0" />';
		echo '<input type="checkbox" id="mailinfo" name="mailinfo" value="1" '.$lastmailinfo.' /><label for="mailinfo">'.get_string('enableemailnotification','assignment').'</label>';
		echo '<div class="buttons">';
		echo '<input type="submit" name="submit" value="'.get_string('savechanges').'" onclick = "document.getElementById(\'submitform\').menuindex.value = document.getElementById(\'submitform\').grade.selectedIndex" />';
		echo '<input type="submit" name="cancel" value="'.get_string('cancel').'" />';
		//if there are more to be graded.
		if ($nextid) {
			echo '<input type="submit" name="saveandnext" value="'.get_string('saveandnext').'" onclick="saveNext()" />';
			echo '<input type="submit" name="next" value="'.get_string('next').'" onclick="setNext();" />';
		}
		echo '</div>';
		echo '</div></form>';

		$customfeedback = $this->custom_feedbackform($submission, true);
		if (!empty($customfeedback)) {
			echo $customfeedback;
		}

		echo '</td></tr>';

		///End of teacher info row, Start of student info row
		echo '<tr>';
		echo '<td class="picture user">';
		print_user_picture($user, $this->course->id, $user->picture);
		echo '</td>';
		echo '<td class="topic">';
		echo '<div class="from">';
		echo '<div class="fullname">'.fullname($user, true).'</div>';
		if ($submission->timemodified) {
			echo '<div class="time">'.userdate($submission->timemodified).
									 $this->display_lateness($submission->timemodified).'</div>';
		}
		echo '</div>';
		$this->print_user_files($user->id);
		echo '</td>';
		echo '</tr>';

		///End of student info row

		echo '</table>';

		if (!$disabled and $this->usehtmleditor) {
			use_html_editor();
		}

		print_footer('none');
	}

	/**
	 *  Preprocess submission before grading
	 *
	 * Called by display_submission()
	 * The default type does nothing here.
	 * @param $submission object The submission object
	 */
	function preprocess_submission(&$submission) {
	}

	/**
	 *  Display all the submissions ready for grading
	 */
	function display_submissions($message='') {
		global $CFG, $db, $USER;
		require_once($CFG->libdir.'/gradelib.php');

		/* first we check to see if the form has just been submitted
		 * to request user_preference updates
		 */

		if (isset($_POST['updatepref'])){
			$perpage = optional_param('perpage', 10, PARAM_INT);
			$perpage = ($perpage <= 0) ? 10 : $perpage ;
			set_user_preference('assignment_perpage', $perpage);
			set_user_preference('assignment_quickgrade', optional_param('quickgrade', 0, PARAM_BOOL));
		}

		/* next we get perpage and quickgrade (allow quick grade) params
		 * from database
		 */
		$perpage	= get_user_preferences('assignment_perpage', 10);

		$quickgrade = get_user_preferences('assignment_quickgrade', 0);

		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id);

		if (!empty($CFG->enableoutcomes) and !empty($grading_info->outcomes)) {
			$uses_outcomes = true;
		} else {
			$uses_outcomes = false;
		}

		$page	= optional_param('page', 0, PARAM_INT);
		$strsaveallfeedback = get_string('saveallfeedback', 'assignment');

	/// Some shortcuts to make the code read better

		$course	 = $this->course;
		$assignment = $this->assignment;
		$cm		 = $this->cm;

		$tabindex = 1; //tabindex for quick grading tabbing; Not working for dropdowns yet
		add_to_log($course->id, 'assignment', 'view submission', 'submissions.php?id='.$this->cm->id, $this->assignment->id, $this->cm->id);
		$navigation = build_navigation($this->strsubmissions, $this->cm);
		print_header_simple(format_string($this->assignment->name,true), "", $navigation,
				'', '', true, update_module_button($cm->id, $course->id, $this->strassignment), navmenu($course, $cm));

		$course_context = get_context_instance(CONTEXT_COURSE, $course->id);
		if (has_capability('gradereport/grader:view', $course_context) && has_capability('moodle/grade:viewall', $course_context)) {
			echo '<div class="allcoursegrades"><a href="' . $CFG->wwwroot . '/grade/report/grader/index.php?id=' . $course->id . '">'
				. get_string('seeallcoursegrades', 'grades') . '</a></div>';
		}

		if (!empty($message)) {
			echo $message;   // display messages here if any
		}

		$context = get_context_instance(CONTEXT_MODULE, $cm->id);

	/// Check to see if groups are being used in this assignment

		/// find out current groups mode
		$groupmode = groups_get_activity_groupmode($cm);
		$currentgroup = groups_get_activity_group($cm, true);
		groups_print_activity_menu($cm, 'submissions.php?id=' . $this->cm->id);

		/// Get all ppl that are allowed to submit assignments
		if ($users = get_users_by_capability($context, 'mod/assignment:submit', 'u.id', '', '', '', $currentgroup, '', false)) {
			$users = array_keys($users);
		}

		// if groupmembersonly used, remove users who are not in any group
		if ($users and !empty($CFG->enablegroupings) and $cm->groupmembersonly) {
			if ($groupingusers = groups_get_grouping_members($cm->groupingid, 'u.id', 'u.id')) {
				$users = array_intersect($users, array_keys($groupingusers));
			}
		}

		$tablecolumns = array('picture', 'fullname', 'grade', 'submissioncomment', 'timemodified', 'timemarked', 'status', 'finalgrade');
		if ($uses_outcomes) {
			$tablecolumns[] = 'outcome'; // no sorting based on outcomes column
		}

		$tableheaders = array('',
							  get_string('fullname'),
							  get_string('grade'),
							  get_string('comment', 'assignment'),
							  get_string('lastmodified').' ('.$course->student.')',
							  get_string('lastmodified').' ('.$course->teacher.')',
							  get_string('status'),
							  get_string('finalgrade', 'grades'));
		if ($uses_outcomes) {
			$tableheaders[] = get_string('outcome', 'grades');
		}

		require_once($CFG->libdir.'/tablelib.php');
		$table = new flexible_table('mod-assignment-submissions');

		$table->define_columns($tablecolumns);
		$table->define_headers($tableheaders);
		$table->define_baseurl($CFG->wwwroot.'/mod/assignment/submissions.php?id='.$this->cm->id.'&amp;currentgroup='.$currentgroup);

		$table->sortable(true, 'lastname');//sorted by lastname by default
		$table->collapsible(true);
		$table->initialbars(true);

		$table->column_suppress('picture');
		$table->column_suppress('fullname');

		$table->column_class('picture', 'picture');
		$table->column_class('fullname', 'fullname');
		$table->column_class('grade', 'grade');
		$table->column_class('submissioncomment', 'comment');
		$table->column_class('timemodified', 'timemodified');
		$table->column_class('timemarked', 'timemarked');
		$table->column_class('status', 'status');
		$table->column_class('finalgrade', 'finalgrade');
		if ($uses_outcomes) {
			$table->column_class('outcome', 'outcome');
		}

		$table->set_attribute('cellspacing', '0');
		$table->set_attribute('id', 'attempts');
		$table->set_attribute('class', 'submissions');
		$table->set_attribute('width', '100%');
		//$table->set_attribute('align', 'center');

		$table->no_sorting('finalgrade');
		$table->no_sorting('outcome');

		// Start working -- this is necessary as soon as the niceties are over
		$table->setup();

		if (empty($users)) {
			print_heading(get_string('nosubmitusers','assignment'));
			return true;
		}

	/// Construct the SQL

		if ($where = $table->get_sql_where()) {
			$where .= ' AND ';
		}

		if ($sort = $table->get_sql_sort()) {
			$sort = ' ORDER BY '.$sort;
		}

		$select = 'SELECT u.id, u.firstname, u.lastname, u.picture, u.imagealt,
						  s.id AS submissionid, s.grade, s.submissioncomment,
						  s.timemodified, s.timemarked,
						  COALESCE(SIGN(SIGN(s.timemarked) + SIGN(s.timemarked - s.timemodified)), 0) AS status ';
		$sql = 'FROM '.$CFG->prefix.'user u '.
			   'LEFT JOIN '.$CFG->prefix.'assignment_submissions s ON u.id = s.userid
																  AND s.assignment = '.$this->assignment->id.' '.
			   'WHERE '.$where.'u.id IN ('.implode(',',$users).') ';

		$table->pagesize($perpage, count($users));

		///offset used to calculate index of student in that particular query, needed for the pop up to know who's next
		$offset = $page * $perpage;

		$strupdate = get_string('update');
		$strgrade  = get_string('grade');
		$grademenu = make_grades_menu($this->assignment->grade);

		if (($ausers = get_records_sql($select.$sql.$sort, $table->get_page_start(), $table->get_page_size())) !== false) {
			$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, array_keys($ausers));
			foreach ($ausers as $auser) {
				$final_grade = $grading_info->items[0]->grades[$auser->id];
				$grademax = $grading_info->items[0]->grademax;
				$final_grade->formatted_grade = round($final_grade->grade,2) .' / ' . round($grademax,2);
				$locked_overridden = 'locked';
				if ($final_grade->overridden) {
					$locked_overridden = 'overridden';
				}

			/// Calculate user status
				$auser->status = ($auser->timemarked > 0) && ($auser->timemarked >= $auser->timemodified);
				$picture = print_user_picture($auser, $course->id, $auser->picture, false, true);

				if (empty($auser->submissionid)) {
					$auser->grade = -1; //no submission yet
				}

				if (!empty($auser->submissionid)) {
				///Prints student answer and student modified date
				///attach file or print link to student answer, depending on the type of the assignment.
				///Refer to print_student_answer in inherited classes.
					if ($auser->timemodified > 0) {
						$studentmodified = '<div id="ts'.$auser->id.'">'.$this->print_student_answer($auser->id)
										 . userdate($auser->timemodified).'</div>';
					} else {
						$studentmodified = '<div id="ts'.$auser->id.'">&nbsp;</div>';
					}
				///Print grade, dropdown or text
					if ($auser->timemarked > 0) {
						$teachermodified = '<div id="tt'.$auser->id.'">'.userdate($auser->timemarked).'</div>';

						if ($final_grade->locked or $final_grade->overridden) {
							$grade = '<div id="g'.$auser->id.'" class="'. $locked_overridden .'">'.$final_grade->formatted_grade.'</div>';
						} else if ($quickgrade) {
							$menu = choose_from_menu(make_grades_menu($this->assignment->grade),
													 'menu['.$auser->id.']', $auser->grade,
													 get_string('nograde'),'',-1,true,false,$tabindex++);
							$grade = '<div id="g'.$auser->id.'">'. $menu .'</div>';
						} else {
							$grade = '<div id="g'.$auser->id.'">'.$this->display_grade($auser->grade).'</div>';
						}

					} else {
						$teachermodified = '<div id="tt'.$auser->id.'">&nbsp;</div>';
						if ($final_grade->locked or $final_grade->overridden) {
							$grade = '<div id="g'.$auser->id.'" class="'. $locked_overridden .'">'.$final_grade->formatted_grade.'</div>';
						} else if ($quickgrade) {
							$menu = choose_from_menu(make_grades_menu($this->assignment->grade),
													 'menu['.$auser->id.']', $auser->grade,
													 get_string('nograde'),'',-1,true,false,$tabindex++);
							$grade = '<div id="g'.$auser->id.'">'.$menu.'</div>';
						} else {
							$grade = '<div id="g'.$auser->id.'">'.$this->display_grade($auser->grade).'</div>';
						}
					}
				///Print Comment
					if ($final_grade->locked or $final_grade->overridden) {
						$comment = '<div id="com'.$auser->id.'">'.shorten_text(strip_tags($final_grade->str_feedback),15).'</div>';

					} else if ($quickgrade) {
						$comment = '<div id="com'.$auser->id.'">'
								 . '<textarea tabindex="'.$tabindex++.'" name="submissioncomment['.$auser->id.']" id="submissioncomment'
								 . $auser->id.'" rows="2" cols="20">'.($auser->submissioncomment).'</textarea></div>';
					} else {
						$comment = '<div id="com'.$auser->id.'">'.shorten_text(strip_tags($auser->submissioncomment),15).'</div>';
					}
				} else {
					$studentmodified = '<div id="ts'.$auser->id.'">&nbsp;</div>';
					$teachermodified = '<div id="tt'.$auser->id.'">&nbsp;</div>';
					$status		  = '<div id="st'.$auser->id.'">&nbsp;</div>';

					if ($final_grade->locked or $final_grade->overridden) {
						$grade = '<div id="g'.$auser->id.'">'.$final_grade->formatted_grade . '</div>';
					} else if ($quickgrade) {   // allow editing
						$menu = choose_from_menu(make_grades_menu($this->assignment->grade),
												 'menu['.$auser->id.']', $auser->grade,
												 get_string('nograde'),'',-1,true,false,$tabindex++);
						$grade = '<div id="g'.$auser->id.'">'.$menu.'</div>';
					} else {
						$grade = '<div id="g'.$auser->id.'">-</div>';
					}

					if ($final_grade->locked or $final_grade->overridden) {
						$comment = '<div id="com'.$auser->id.'">'.$final_grade->str_feedback.'</div>';
					} else if ($quickgrade) {
						$comment = '<div id="com'.$auser->id.'">'
								 . '<textarea tabindex="'.$tabindex++.'" name="submissioncomment['.$auser->id.']" id="submissioncomment'
								 . $auser->id.'" rows="2" cols="20">'.($auser->submissioncomment).'</textarea></div>';
					} else {
						$comment = '<div id="com'.$auser->id.'">&nbsp;</div>';
					}
				}

				if (empty($auser->status)) { /// Confirm we have exclusively 0 or 1
					$auser->status = 0;
				} else {
					$auser->status = 1;
				}

				$buttontext = ($auser->status == 1) ? $strupdate : $strgrade;

				///No more buttons, we use popups ;-).
				$popup_url = '/mod/assignment/submissions.php?id='.$this->cm->id
						   . '&amp;userid='.$auser->id.'&amp;mode=single'.'&amp;offset='.$offset++;
				$button = link_to_popup_window ($popup_url, 'grade'.$auser->id, $buttontext, 600, 780,
												$buttontext, 'none', true, 'button'.$auser->id);

				$status  = '<div id="up'.$auser->id.'" class="s'.$auser->status.'">'.$button.'</div>';

				$finalgrade = '<span id="finalgrade_'.$auser->id.'">'.$final_grade->str_grade.'</span>';

				$outcomes = '';

				if ($uses_outcomes) {

					foreach($grading_info->outcomes as $n=>$outcome) {
						$outcomes .= '<div class="outcome"><label>'.$outcome->name.'</label>';
						$options = make_grades_menu(-$outcome->scaleid);

						if ($outcome->grades[$auser->id]->locked or !$quickgrade) {
							$options[0] = get_string('nooutcome', 'grades');
							$outcomes .= ': <span id="outcome_'.$n.'_'.$auser->id.'">'.$options[$outcome->grades[$auser->id]->grade].'</span>';
						} else {
							$outcomes .= ' ';
							$outcomes .= choose_from_menu($options, 'outcome_'.$n.'['.$auser->id.']',
										$outcome->grades[$auser->id]->grade, get_string('nooutcome', 'grades'), '', 0, true, false, 0, 'outcome_'.$n.'_'.$auser->id);
						}
						$outcomes .= '</div>';
					}
				}

				$userlink = '<a href="' . $CFG->wwwroot . '/user/view.php?id=' . $auser->id . '&amp;course=' . $course->id . '">' . fullname($auser) . '</a>';
				$row = array($picture, $userlink, $grade, $comment, $studentmodified, $teachermodified, $status, $finalgrade);
				if ($uses_outcomes) {
					$row[] = $outcomes;
				}

				$table->add_data($row);
			}
		}

		/// Print quickgrade form around the table
		if ($quickgrade){
			echo '<form action="submissions.php" id="fastg" method="post">';
			echo '<div>';
			echo '<input type="hidden" name="id" value="'.$this->cm->id.'" />';
			echo '<input type="hidden" name="mode" value="fastgrade" />';
			echo '<input type="hidden" name="page" value="'.$page.'" />';
			echo '</div>';
		}

		$table->print_html();  /// Print the whole table

		if ($quickgrade){
			$lastmailinfo = get_user_preferences('assignment_mailinfo', 1) ? 'checked="checked"' : '';
			echo '<div class="fgcontrols">';
			echo '<div class="emailnotification">';
			echo '<label for="mailinfo">'.get_string('enableemailnotification','assignment').'</label>';
			echo '<input type="hidden" name="mailinfo" value="0" />';
			echo '<input type="checkbox" id="mailinfo" name="mailinfo" value="1" '.$lastmailinfo.' />';
			helpbutton('emailnotification', get_string('enableemailnotification', 'assignment'), 'assignment').'</p></div>';
			echo '</div>';
			echo '<div class="fastgbutton"><input type="submit" name="fastg" value="'.get_string('saveallfeedback', 'assignment').'" /></div>';
			echo '</div>';
			echo '</form>';
		}
		/// End of fast grading form

		/// Mini form for setting user preference
		echo '<div class="qgprefs">';
		echo '<form id="options" action="submissions.php?id='.$this->cm->id.'" method="post"><div>';
		echo '<input type="hidden" name="updatepref" value="1" />';
		echo '<table id="optiontable">';
		echo '<tr><td>';
		echo '<label for="perpage">'.get_string('pagesize','assignment').'</label>';
		echo '</td>';
		echo '<td>';
		echo '<input type="text" id="perpage" name="perpage" size="1" value="'.$perpage.'" />';
		helpbutton('pagesize', get_string('pagesize','assignment'), 'assignment');
		echo '</td></tr>';
		echo '<tr><td>';
		echo '<label for="quickgrade">'.get_string('quickgrade','assignment').'</label>';
		echo '</td>';
		echo '<td>';
		$checked = $quickgrade ? 'checked="checked"' : '';
		echo '<input type="checkbox" id="quickgrade" name="quickgrade" value="1" '.$checked.' />';
		helpbutton('quickgrade', get_string('quickgrade', 'assignment'), 'assignment').'</p></div>';
		echo '</td></tr>';
		echo '<tr><td colspan="2">';
		echo '<input type="submit" value="'.get_string('savepreferences').'" />';
		echo '</td></tr></table>';
		echo '</div></form></div>';
		///End of mini form
		print_footer($this->course);
	}

	/**
	 *  Process teacher feedback submission
	 *
	 * This is called by submissions() when a grading even has taken place.
	 * It gets its data from the submitted form.
	 * @return object The updated submission object
	 */
	function process_feedback() {
		global $CFG, $USER;
		require_once($CFG->libdir.'/gradelib.php');

		if (!$feedback = data_submitted()) {	  // No incoming data?
			return false;
		}

		///For save and next, we need to know the userid to save, and the userid to go
		///We use a new hidden field in the form, and set it to -1. If it's set, we use this
		///as the userid to store
		if ((int)$feedback->saveuserid !== -1){
			$feedback->userid = $feedback->saveuserid;
		}

		if (!empty($feedback->cancel)) {		  // User hit cancel button
			return false;
		}

		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, $feedback->userid);

		// store outcomes if needed
		$this->process_outcomes($feedback->userid);

		$submission = $this->get_submission($feedback->userid, true);  // Get or make one

		if (!$grading_info->items[0]->grades[$feedback->userid]->locked and
			!$grading_info->items[0]->grades[$feedback->userid]->overridden) {

			$submission->grade	  = $feedback->grade;
			$submission->submissioncomment	= $feedback->submissioncomment;
			$submission->format	 = $feedback->format;
			$submission->teacher	= $USER->id;
			$mailinfo = get_user_preferences('assignment_mailinfo', 0);
			if (!$mailinfo) {
				$submission->mailed = 1;	   // treat as already mailed
			} else {
				$submission->mailed = 0;	   // Make sure mail goes out (again, even)
			}
			$submission->timemarked = time();

			unset($submission->data1);  // Don't need to update this.
			unset($submission->data2);  // Don't need to update this.

			if (empty($submission->timemodified)) {   // eg for offline assignments
				// $submission->timemodified = time();
			}

			if (! update_record('assignment_submissions', $submission)) {
				return false;
			}

			// triger grade event
			$this->update_grade($submission);

			add_to_log($this->course->id, 'assignment', 'update grades',
					   'submissions.php?id='.$this->assignment->id.'&user='.$feedback->userid, $feedback->userid, $this->cm->id);
		}

		return $submission;

	}

	function process_outcomes($userid) {
		global $CFG, $USER;

		if (empty($CFG->enableoutcomes)) {
			return;
		}

		require_once($CFG->libdir.'/gradelib.php');

		if (!$formdata = data_submitted()) {
			return;
		}

		$data = array();
		$grading_info = grade_get_grades($this->course->id, 'mod', 'assignment', $this->assignment->id, $userid);

		if (!empty($grading_info->outcomes)) {
			foreach($grading_info->outcomes as $n=>$old) {
				$name = 'outcome_'.$n;
				if (isset($formdata->{$name}[$userid]) and $old->grades[$userid]->grade != $formdata->{$name}[$userid]) {
					$data[$n] = $formdata->{$name}[$userid];
				}
			}
		}
		if (count($data) > 0) {
			grade_update_outcomes('mod/assignment', $this->course->id, 'mod', 'assignment', $this->assignment->id, $userid, $data);
		}

	}

	/**
	 * Load the submission object for a particular user
	 *
	 * @param $userid int The id of the user whose submission we want or 0 in which case USER->id is used
	 * @param $createnew boolean optional Defaults to false. If set to true a new submission object will be created in the database
	 * @param bool $teachermodified student submission set if false
	 * @return object The submission
	 */
	function get_submission($userid=0, $createnew=false, $teachermodified=false) {
		global $USER;

		if (empty($userid)) {
			$userid = $USER->id;
		}

		$submission = get_record('assignment_submissions', 'assignment', $this->assignment->id, 'userid', $userid);

		if ($submission || !$createnew) {
			return $submission;
		}
		$newsubmission = $this->prepare_new_submission($userid, $teachermodified);
		if (!insert_record("assignment_submissions", $newsubmission)) {
			error("Could not insert a new empty submission");
		}

		return get_record('assignment_submissions', 'assignment', $this->assignment->id, 'userid', $userid);
	}

	/**
	 * Instantiates a new submission object for a given user
	 *
	 * Sets the assignment, userid and times, everything else is set to default values.
	 * @param $userid int The userid for which we want a submission object
	 * @param bool $teachermodified student submission set if false
	 * @return object The submission
	 */
	function prepare_new_submission($userid, $teachermodified=false) {
		$submission = new Object;
		$submission->assignment   = $this->assignment->id;
		$submission->userid	   = $userid;
		//$submission->timecreated  = time();
		$submission->timecreated = '';
		// teachers should not be modifying modified date, except offline assignments
		if ($teachermodified) {
			$submission->timemodified = 0;
		} else {
			$submission->timemodified = $submission->timecreated;
		}
		$submission->numfiles	 = 0;
		$submission->data1		= '';
		$submission->data2		= '';
		$submission->grade		= -1;
		$submission->submissioncomment	  = '';
		$submission->format	   = 0;
		$submission->teacher	  = 0;
		$submission->timemarked   = 0;
		$submission->mailed	   = 0;
		return $submission;
	}

	/**
	 * Return all assignment submissions by ENROLLED students (even empty)
	 *
	 * @param $sort string optional field names for the ORDER BY in the sql query
	 * @param $dir string optional specifying the sort direction, defaults to DESC
	 * @return array The submission objects indexed by id
	 */
	function get_submissions($sort='', $dir='DESC') {
		return assignment_get_all_submissions($this->assignment, $sort, $dir);
	}

	/**
	 * Counts all real assignment submissions by ENROLLED students (not empty ones)
	 *
	 * @param $groupid int optional If nonzero then count is restricted to this group
	 * @return int The number of submissions
	 */
	function count_real_submissions($groupid=0) {
		return assignment_count_real_submissions($this->cm, $groupid);
	}

	/**
	 * Alerts teachers by email of new or changed assignments that need grading
	 *
	 * First checks whether the option to email teachers is set for this assignment.
	 * Sends an email to ALL teachers in the course (or in the group if using separate groups).
	 * Uses the methods email_teachers_text() and email_teachers_html() to construct the content.
	 * @param $submission object The submission that has changed
	 */
	function email_teachers($submission) {
		global $CFG;

		if (empty($this->assignment->emailteachers)) {		  // No need to do anything
			return;
		}

		$user = get_record('user', 'id', $submission->userid);

		if ($teachers = $this->get_graders($user)) {

			$strassignments = get_string('modulenameplural', 'assignment');
			$strassignment  = get_string('modulename', 'assignment');
			$strsubmitted  = get_string('submitted', 'assignment');

			foreach ($teachers as $teacher) {
				$info = new object();
				$info->username = fullname($user, true);
				$info->assignment = format_string($this->assignment->name,true);
				$info->url = $CFG->wwwroot.'/mod/assignment/submissions.php?id='.$this->cm->id;

				$postsubject = $strsubmitted.': '.$info->username.' -> '.$this->assignment->name;
				$posttext = $this->email_teachers_text($info);
				$posthtml = ($teacher->mailformat == 1) ? $this->email_teachers_html($info) : '';

				@email_to_user($teacher, $user, $postsubject, $posttext, $posthtml);  // If it fails, oh well, too bad.
			}
		}
	}

	/**
	 * Returns a list of teachers that should be grading given submission
	 */
	function get_graders($user) {
		//potential graders
		$potgraders = get_users_by_capability($this->context, 'mod/assignment:grade', '', '', '', '', '', '', false, false);

		$graders = array();
		if (groups_get_activity_groupmode($this->cm) == SEPARATEGROUPS) {   // Separate groups are being used
			if ($groups = groups_get_all_groups($this->course->id, $user->id)) {  // Try to find all groups
				foreach ($groups as $group) {
					foreach ($potgraders as $t) {
						if ($t->id == $user->id) {
							continue; // do not send self
						}
						if (groups_is_member($group->id, $t->id)) {
							$graders[$t->id] = $t;
						}
					}
				}
			} else {
				// user not in group, try to find graders without group
				foreach ($potgraders as $t) {
					if ($t->id == $user->id) {
						continue; // do not send self
					}
					if (!groups_get_all_groups($this->course->id, $t->id)) { //ugly hack
						$graders[$t->id] = $t;
					}
				}
			}
		} else {
			foreach ($potgraders as $t) {
				if ($t->id == $user->id) {
					continue; // do not send self
				}
				$graders[$t->id] = $t;
			}
		}
		return $graders;
	}

	/**
	 * Creates the text content for emails to teachers
	 *
	 * @param $info object The info used by the 'emailteachermail' language string
	 * @return string
	 */
	function email_teachers_text($info) {
		$posttext  = format_string($this->course->shortname).' -> '.$this->strassignments.' -> '.
					 format_string($this->assignment->name)."\n";
		$posttext .= '---------------------------------------------------------------------'."\n";
		$posttext .= get_string("emailteachermail", "assignment", $info)."\n";
		$posttext .= "\n---------------------------------------------------------------------\n";
		return $posttext;
	}

	 /**
	 * Creates the html content for emails to teachers
	 *
	 * @param $info object The info used by the 'emailteachermailhtml' language string
	 * @return string
	 */
	function email_teachers_html($info) {
		global $CFG;
		$posthtml  = '<p><font face="sans-serif">'.
					 '<a href="'.$CFG->wwwroot.'/course/view.php?id='.$this->course->id.'">'.format_string($this->course->shortname).'</a> ->'.
					 '<a href="'.$CFG->wwwroot.'/mod/assignment/index.php?id='.$this->course->id.'">'.$this->strassignments.'</a> ->'.
					 '<a href="'.$CFG->wwwroot.'/mod/assignment/view.php?id='.$this->cm->id.'">'.format_string($this->assignment->name).'</a></font></p>';
		$posthtml .= '<hr /><font face="sans-serif">';
		$posthtml .= '<p>'.get_string('emailteachermailhtml', 'assignment', $info).'</p>';
		$posthtml .= '</font><hr />';
		return $posthtml;
	}

	/**
	 * Produces a list of links to the files uploaded by a user
	 *
	 * @param $userid int optional id of the user. If 0 then $USER->id is used.
	 * @param $return boolean optional defaults to false. If true the list is returned rather than printed
	 * @return string optional
	 */
	function print_user_files($userid=0, $return=false) {
		global $CFG, $USER;

		if (!$userid) {
			if (!isloggedin()) {
				return '';
			}
			$userid = $USER->id;
		}

		$filearea = $this->file_area_name($userid);

		$output = '';

		if ($basedir = $this->file_area($userid)) {
			if ($files = get_directory_list($basedir)) {
				require_once($CFG->libdir.'/filelib.php');
				foreach ($files as $key => $file) {

					$icon = mimeinfo('icon', $file);
					$ffurl = get_file_url("$filearea/$file", array('forcedownload'=>1));

					$output .= '<img src="'.$CFG->pixpath.'/f/'.$icon.'" class="icon" alt="'.$icon.'" />'.
							'<a href="'.$ffurl.'" >'.$file.'</a><br />';
				}
			}
		}

		$output = '<div class="files">'.$output.'</div>';

		if ($return) {
			return $output;
		}
		echo $output;
	}

	/**
	 * Count the files uploaded by a given user
	 *
	 * @param $userid int The user id
	 * @return int
	 */
	function count_user_files($userid) {
		global $CFG;

		$filearea = $this->file_area_name($userid);

		if ( is_dir($CFG->dataroot.'/'.$filearea) && $basedir = $this->file_area($userid)) {
			if ($files = get_directory_list($basedir)) {
				return count($files);
			}
		}
		return 0;
	}

	/**
	 * Creates a directory file name, suitable for make_upload_directory()
	 *
	 * @param $userid int The user id
	 * @return string path to file area
	 */
	function file_area_name($userid) {
		global $CFG;

		return $this->course->id.'/'.$CFG->moddata.'/assignment/'.$this->assignment->id.'/'.$userid;
	}

	/**
	 * Makes an upload directory
	 *
	 * @param $userid int The user id
	 * @return string path to file area.
	 */
	function file_area($userid) {
		return make_upload_directory( $this->file_area_name($userid) );
	}

	/**
	 * Returns true if the student is allowed to submit
	 *
	 * Checks that the assignment has started and, if the option to prevent late
	 * submissions is set, also checks that the assignment has not yet closed.
	 * @return boolean
	 */
	function isopen() {
		$time = time();
		if ($this->assignment->preventlate && $this->assignment->timedue) {
			return ($this->assignment->timeavailable <= $time && $time <= $this->assignment->timedue);
		} else {
			return ($this->assignment->timeavailable <= $time);
		}
	}


	/**
	 * Return true if is set description is hidden till available date
	 *
	 * This is needed by calendar so that hidden descriptions do not
	 * come up in upcoming events.
	 *
	 * Check that description is hidden till available date
	 * By default return false
	 * Assignments types should implement this method if needed
	 * @return boolen
	 */
	function description_is_hidden() {
		return false;
	}

	/**
	 * Return an outline of the user's interaction with the assignment
	 *
	 * The default method prints the grade and timemodified
	 * @param $user object
	 * @return object with properties ->info and ->time
	 */
	function user_outline($user) {
		if ($submission = $this->get_submission($user->id)) {

			$result = new object();
			$result->info = get_string('grade').': '.$this->display_grade($submission->grade);
			$result->time = $submission->timemodified;
			return $result;
		}
		return NULL;
	}

	/**
	 * Print complete information about the user's interaction with the assignment
	 *
	 * @param $user object
	 */
	function user_complete($user) {
		if ($submission = $this->get_submission($user->id)) {
			if ($basedir = $this->file_area($user->id)) {
				if ($files = get_directory_list($basedir)) {
					$countfiles = count($files)." ".get_string("uploadedfiles", "assignment");
					foreach ($files as $file) {
						$countfiles .= "; $file";
					}
				}
			}

			print_simple_box_start();
			echo get_string("lastmodified").": ";
			echo userdate($submission->timemodified);
			echo $this->display_lateness($submission->timemodified);

			$this->print_user_files($user->id);

			echo '<br />';

			if (empty($submission->timemarked)) {
				print_string("notgradedyet", "assignment");
			} else {
				$this->view_feedback($submission);
			}

			print_simple_box_end();

		} else {
			print_string("notsubmittedyet", "assignment");
		}
	}

	/**
	 * Return a string indicating how late a submission is
	 *
	 * @param $timesubmitted int
	 * @return string
	 */
	function display_lateness($timesubmitted) {
		return assignment_display_lateness($timesubmitted, $this->assignment->timedue);
	}

	/**
	 * Empty method stub for all delete actions.
	 */
	function delete() {
		//nothing by default
		redirect('view.php?id='.$this->cm->id);
	}

	/**
	 * Empty custom feedback grading form.
	 */
	function custom_feedbackform($submission, $return=false) {
		//nothing by default
		return '';
	}

	/**
	 * Add a get_coursemodule_info function in case any assignment type wants to add 'extra' information
	 * for the course (see resource).
	 *
	 * Given a course_module object, this function returns any "extra" information that may be needed
	 * when printing this activity in a course listing.  See get_array_of_activities() in course/lib.php.
	 *
	 * @param $coursemodule object The coursemodule object (record).
	 * @return object An object on information that the coures will know about (most noticeably, an icon).
	 *
	 */
	function get_coursemodule_info($coursemodule) {
		return false;
	}

	/**
	 * Plugin cron method - do not use $this here, create new assignment instances if needed.
	 * @return void
	 */
	function cron() {
		//no plugin cron by default - override if needed
	}

	/**
	 * Reset all submissions
	 */
	function reset_userdata($data) {
		global $CFG;
		require_once($CFG->libdir.'/filelib.php');

		if (!count_records('assignment', 'course', $data->courseid, 'assignmenttype', $this->type)) {
			return array(); // no assignments of this type present
		}

		$componentstr = get_string('modulenameplural', 'assignment');
		$status = array();

		$typestr = get_string('type'.$this->type, 'assignment');

		if (!empty($data->reset_assignment_submissions)) {
			$assignmentssql = "SELECT a.id
								 FROM {$CFG->prefix}assignment a
								WHERE a.course={$data->courseid} AND a.assignmenttype='{$this->type}'";

			delete_records_select('assignment_submissions', "assignment IN ($assignmentssql)");

			if ($assignments = get_records_sql($assignmentssql)) {
				foreach ($assignments as $assignmentid=>$unused) {
					fulldelete($CFG->dataroot.'/'.$data->courseid.'/moddata/assignment/'.$assignmentid);
				}
			}

			$status[] = array('component'=>$componentstr, 'item'=>get_string('deleteallsubmissions','assignment').': '.$typestr, 'error'=>false);

			if (empty($data->reset_gradebook_grades)) {
				// remove all grades from gradebook
				assignment_reset_gradebook($data->courseid, $this->type);
			}
		}

		/// updating dates - shift may be negative too
		if ($data->timeshift) {
			shift_course_mod_dates('assignment', array('timedue', 'timeavailable'), $data->timeshift, $data->courseid);
			$status[] = array('component'=>$componentstr, 'item'=>get_string('datechanged').': '.$typestr, 'error'=>false);
		}

		return $status;
	}
} ////// End of the assignment_base class



/// OTHER STANDARD FUNCTIONS ////////////////////////////////////////////////////////

/**
 * Deletes an assignment instance
 *
 * This is done by calling the delete_instance() method of the assignment type class
 */
function assignment_delete_instance($id){
	global $CFG;

	if (! $assignment = get_record('assignment', 'id', $id)) {
		return false;
	}

	// fall back to base class if plugin missing
	$classfile = "$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php";
	if (file_exists($classfile)) {
		require_once($classfile);
		$assignmentclass = "assignment_$assignment->assignmenttype";

	} else {
		debugging("Missing assignment plug-in: {$assignment->assignmenttype}. Using base class for deleting instead.");
		$assignmentclass = "assignment_base";
	}

	$ass = new $assignmentclass();
	return $ass->delete_instance($assignment);
}


/**
 * Updates an assignment instance
 *
 * This is done by calling the update_instance() method of the assignment type class
 */
function assignment_update_instance($assignment){
	global $CFG;

	$assignment->assignmenttype = clean_param($assignment->assignmenttype, PARAM_SAFEDIR);

	require_once("$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php");
	$assignmentclass = "assignment_$assignment->assignmenttype";
	$ass = new $assignmentclass();
	return $ass->update_instance($assignment);
}


/**
 * Adds an assignment instance
 *
 * This is done by calling the add_instance() method of the assignment type class
 */
function assignment_add_instance($assignment) {
	global $CFG;

	$assignment->assignmenttype = clean_param($assignment->assignmenttype, PARAM_SAFEDIR);

	require_once("$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php");
	$assignmentclass = "assignment_$assignment->assignmenttype";
	$ass = new $assignmentclass();
	return $ass->add_instance($assignment);
}


/**
 * Returns an outline of a user interaction with an assignment
 *
 * This is done by calling the user_outline() method of the assignment type class
 */
function assignment_user_outline($course, $user, $mod, $assignment) {
	global $CFG;

	require_once("$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php");
	$assignmentclass = "assignment_$assignment->assignmenttype";
	$ass = new $assignmentclass($mod->id, $assignment, $mod, $course);
	return $ass->user_outline($user);
}

/**
 * Prints the complete info about a user's interaction with an assignment
 *
 * This is done by calling the user_complete() method of the assignment type class
 */
function assignment_user_complete($course, $user, $mod, $assignment) {
	global $CFG;

	require_once("$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php");
	$assignmentclass = "assignment_$assignment->assignmenttype";
	$ass = new $assignmentclass($mod->id, $assignment, $mod, $course);
	return $ass->user_complete($user);
}

/**
 * Function to be run periodically according to the moodle cron
 *
 * Finds all assignment notifications that have yet to be mailed out, and mails them
 */
function assignment_cron () {

	global $CFG, $USER;

	/// first execute all crons in plugins
	if ($plugins = get_list_of_plugins('mod/assignment/type')) {
		foreach ($plugins as $plugin) {
			require_once("$CFG->dirroot/mod/assignment/type/$plugin/assignment.class.php");
			$assignmentclass = "assignment_$plugin";
			$ass = new $assignmentclass();
			$ass->cron();
		}
	}

	/// Notices older than 1 day will not be mailed.  This is to avoid the problem where
	/// cron has not been running for a long time, and then suddenly people are flooded
	/// with mail from the past few weeks or months

	$timenow   = time();
	$endtime   = $timenow - $CFG->maxeditingtime;
	$starttime = $endtime - 24 * 3600;   /// One day earlier

	if ($submissions = assignment_get_unmailed_submissions($starttime, $endtime)) {

		$realuser = clone($USER);

		foreach ($submissions as $key => $submission) {
			if (! set_field("assignment_submissions", "mailed", "1", "id", "$submission->id")) {
				echo "Could not update the mailed field for id $submission->id.  Not mailed.\n";
				unset($submissions[$key]);
			}
		}

		$timenow = time();

		foreach ($submissions as $submission) {

			echo "Processing assignment submission $submission->id\n";

			if (! $user = get_record("user", "id", "$submission->userid")) {
				echo "Could not find user $post->userid\n";
				continue;
			}

			if (! $course = get_record("course", "id", "$submission->course")) {
				echo "Could not find course $submission->course\n";
				continue;
			}

			/// Override the language and timezone of the "current" user, so that
			/// mail is customised for the receiver.
			$USER = $user;
			course_setup($course);

			if (!has_capability('moodle/course:view', get_context_instance(CONTEXT_COURSE, $submission->course), $user->id)) {
				echo fullname($user)." not an active participant in " . format_string($course->shortname) . "\n";
				continue;
			}

			if (! $teacher = get_record("user", "id", "$submission->teacher")) {
				echo "Could not find teacher $submission->teacher\n";
				continue;
			}

			if (! $mod = get_coursemodule_from_instance("assignment", $submission->assignment, $course->id)) {
				echo "Could not find course module for assignment id $submission->assignment\n";
				continue;
			}

			if (! $mod->visible) {	/// Hold mail notification for hidden assignments until later
				continue;
			}

			$strassignments = get_string("modulenameplural", "assignment");
			$strassignment  = get_string("modulename", "assignment");

			$assignmentinfo = new object();
			$assignmentinfo->teacher = fullname($teacher);
			$assignmentinfo->assignment = format_string($submission->name,true);
			$assignmentinfo->url = "$CFG->wwwroot/mod/assignment/view.php?id=$mod->id";

			$postsubject = "$course->shortname: $strassignments: ".format_string($submission->name,true);
			$posttext  = "$course->shortname -> $strassignments -> ".format_string($submission->name,true)."\n";
			$posttext .= "---------------------------------------------------------------------\n";
			$posttext .= get_string("assignmentmail", "assignment", $assignmentinfo)."\n";
			$posttext .= "---------------------------------------------------------------------\n";

			if ($user->mailformat == 1) {  // HTML
				$posthtml = "<p><font face=\"sans-serif\">".
				"<a href=\"$CFG->wwwroot/course/view.php?id=$course->id\">$course->shortname</a> ->".
				"<a href=\"$CFG->wwwroot/mod/assignment/index.php?id=$course->id\">$strassignments</a> ->".
				"<a href=\"$CFG->wwwroot/mod/assignment/view.php?id=$mod->id\">".format_string($submission->name,true)."</a></font></p>";
				$posthtml .= "<hr /><font face=\"sans-serif\">";
				$posthtml .= "<p>".get_string("assignmentmailhtml", "assignment", $assignmentinfo)."</p>";
				$posthtml .= "</font><hr />";
			} else {
				$posthtml = "";
			}

			if (! email_to_user($user, $teacher, $postsubject, $posttext, $posthtml)) {
				echo "Error: assignment cron: Could not send out mail for id $submission->id to user $user->id ($user->email)\n";
			}
		}

		$USER = $realuser;
		course_setup(SITEID); // reset cron user language, theme and timezone settings

	}

	return true;
}

/**
 * Return grade for given user or all users.
 *
 * @param int $assignmentid id of assignment
 * @param int $userid optional user id, 0 means all users
 * @return array array of grades, false if none
 */
function assignment_get_user_grades($assignment, $userid=0) {
	global $CFG;

	$user = $userid ? "AND u.id = $userid" : "";

	$sql = "SELECT u.id, u.id AS userid, s.grade AS rawgrade, s.submissioncomment AS feedback, s.format AS feedbackformat,
				   s.teacher AS usermodified, s.timemarked AS dategraded, s.timemodified AS datesubmitted
			  FROM {$CFG->prefix}user u, {$CFG->prefix}assignment_submissions s
			 WHERE u.id = s.userid AND s.assignment = $assignment->id
				   $user";

	return get_records_sql($sql);
}

/**
 * Update grades by firing grade_updated event
 *
 * @param object $assignment null means all assignments
 * @param int $userid specific user only, 0 mean all
 */
function assignment_update_grades($assignment=null, $userid=0, $nullifnone=true) {
	global $CFG;
	if (!function_exists('grade_update')) { //workaround for buggy PHP versions
		require_once($CFG->libdir.'/gradelib.php');
	}

	if ($assignment != null) {
		if ($grades = assignment_get_user_grades($assignment, $userid)) {
			foreach($grades as $k=>$v) {
				if ($v->rawgrade == -1) {
					$grades[$k]->rawgrade = null;
				}
			}
			assignment_grade_item_update($assignment, $grades);
		} else {
			assignment_grade_item_update($assignment);
		}

	} else {
		$sql = "SELECT a.*, cm.idnumber as cmidnumber, a.course as courseid
				  FROM {$CFG->prefix}assignment a, {$CFG->prefix}course_modules cm, {$CFG->prefix}modules m
				 WHERE m.name='assignment' AND m.id=cm.module AND cm.instance=a.id";
		if ($rs = get_recordset_sql($sql)) {
			while ($assignment = rs_fetch_next_record($rs)) {
				if ($assignment->grade != 0) {
					assignment_update_grades($assignment);
				} else {
					assignment_grade_item_update($assignment);
				}
			}
			rs_close($rs);
		}
	}
}

/**
 * Create grade item for given assignment
 *
 * @param object $assignment object with extra cmidnumber
 * @param mixed optional array/object of grade(s); 'reset' means reset grades in gradebook
 * @return int 0 if ok, error code otherwise
 */
function assignment_grade_item_update($assignment, $grades=NULL) {
	global $CFG;
	if (!function_exists('grade_update')) { //workaround for buggy PHP versions
		require_once($CFG->libdir.'/gradelib.php');
	}

	if (!isset($assignment->courseid)) {
		$assignment->courseid = $assignment->course;
	}

	$params = array('itemname'=>$assignment->name, 'idnumber'=>$assignment->cmidnumber);

	if ($assignment->grade > 0) {
		$params['gradetype'] = GRADE_TYPE_VALUE;
		$params['grademax']  = $assignment->grade;
		$params['grademin']  = 0;

	} else if ($assignment->grade < 0) {
		$params['gradetype'] = GRADE_TYPE_SCALE;
		$params['scaleid']   = -$assignment->grade;

	} else {
		$params['gradetype'] = GRADE_TYPE_TEXT; // allow text comments only
	}

	if ($grades  === 'reset') {
		$params['reset'] = true;
		$grades = NULL;
	}

	return grade_update('mod/assignment', $assignment->courseid, 'mod', 'assignment', $assignment->id, 0, $grades, $params);
}

/**
 * Delete grade item for given assignment
 *
 * @param object $assignment object
 * @return object assignment
 */
function assignment_grade_item_delete($assignment) {
	global $CFG;
	require_once($CFG->libdir.'/gradelib.php');

	if (!isset($assignment->courseid)) {
		$assignment->courseid = $assignment->course;
	}

	return grade_update('mod/assignment', $assignment->courseid, 'mod', 'assignment', $assignment->id, 0, NULL, array('deleted'=>1));
}

/**
 * Returns the users with data in one assignment (students and teachers)
 *
 * @param $assignmentid int
 * @return array of user objects
 */
function assignment_get_participants($assignmentid) {

	global $CFG;

	//Get students
	$students = get_records_sql("SELECT DISTINCT u.id, u.id
								 FROM {$CFG->prefix}user u,
									  {$CFG->prefix}assignment_submissions a
								 WHERE a.assignment = '$assignmentid' and
									   u.id = a.userid");
	//Get teachers
	$teachers = get_records_sql("SELECT DISTINCT u.id, u.id
								 FROM {$CFG->prefix}user u,
									  {$CFG->prefix}assignment_submissions a
								 WHERE a.assignment = '$assignmentid' and
									   u.id = a.teacher");

	//Add teachers to students
	if ($teachers) {
		foreach ($teachers as $teacher) {
			$students[$teacher->id] = $teacher;
		}
	}
	//Return students array (it contains an array of unique users)
	return ($students);
}

/**
 * Checks if a scale is being used by an assignment
 *
 * This is used by the backup code to decide whether to back up a scale
 * @param $assignmentid int
 * @param $scaleid int
 * @return boolean True if the scale is used by the assignment
 */
function assignment_scale_used($assignmentid, $scaleid) {

	$return = false;

	$rec = get_record('assignment','id',$assignmentid,'grade',-$scaleid);

	if (!empty($rec) && !empty($scaleid)) {
		$return = true;
	}

	return $return;
}

/**
 * Checks if scale is being used by any instance of assignment
 *
 * This is used to find out if scale used anywhere
 * @param $scaleid int
 * @return boolean True if the scale is used by any assignment
 */
function assignment_scale_used_anywhere($scaleid) {
	if ($scaleid and record_exists('assignment', 'grade', -$scaleid)) {
		return true;
	} else {
		return false;
	}
}

/**
 * Make sure up-to-date events are created for all assignment instances
 *
 * This standard function will check all instances of this module
 * and make sure there are up-to-date events created for each of them.
 * If courseid = 0, then every assignment event in the site is checked, else
 * only assignment events belonging to the course specified are checked.
 * This function is used, in its new format, by restore_refresh_events()
 *
 * @param $courseid int optional If zero then all assignments for all courses are covered
 * @return boolean Always returns true
 */
function assignment_refresh_events($courseid = 0) {

	if ($courseid == 0) {
		if (! $assignments = get_records("assignment")) {
			return true;
		}
	} else {
		if (! $assignments = get_records("assignment", "course", $courseid)) {
			return true;
		}
	}
	$moduleid = get_field('modules', 'id', 'name', 'assignment');

	foreach ($assignments as $assignment) {
		$event = NULL;
		$event->name		= addslashes($assignment->name);
		$event->description = addslashes($assignment->description);
		$event->timestart   = $assignment->timedue;

		if ($event->id = get_field('event', 'id', 'modulename', 'assignment', 'instance', $assignment->id)) {
			update_event($event);

		} else {
			$event->courseid	= $assignment->course;
			$event->groupid	 = 0;
			$event->userid	  = 0;
			$event->modulename  = 'assignment';
			$event->instance	= $assignment->id;
			$event->eventtype   = 'due';
			$event->timeduration = 0;
			$event->visible	 = get_field('course_modules', 'visible', 'module', $moduleid, 'instance', $assignment->id);
			add_event($event);
		}

	}
	return true;
}

/**
 * Print recent activity from all assignments in a given course
 *
 * This is used by the recent activity block
 */
function assignment_print_recent_activity($course, $viewfullnames, $timestart) {
	global $CFG, $USER;

	// do not use log table if possible, it may be huge

	if (!$submissions = get_records_sql("SELECT asb.id, asb.timemodified, cm.id AS cmid, asb.userid,
												u.firstname, u.lastname, u.email, u.picture
										   FROM {$CFG->prefix}assignment_submissions asb
												JOIN {$CFG->prefix}assignment a	  ON a.id = asb.assignment
												JOIN {$CFG->prefix}course_modules cm ON cm.instance = a.id
												JOIN {$CFG->prefix}modules md		ON md.id = cm.module
												JOIN {$CFG->prefix}user u			ON u.id = asb.userid
										  WHERE asb.timemodified > $timestart AND
												a.course = {$course->id} AND
												md.name = 'assignment'
									   ORDER BY asb.timemodified ASC")) {
		 return false;
	}

	$modinfo =& get_fast_modinfo($course); // reference needed because we might load the groups
	$show	= array();
	$grader  = array();

	foreach($submissions as $submission) {
		if (!array_key_exists($submission->cmid, $modinfo->cms)) {
			continue;
		}
		$cm = $modinfo->cms[$submission->cmid];
		if (!$cm->uservisible) {
			continue;
		}
		if ($submission->userid == $USER->id) {
			$show[] = $submission;
			continue;
		}

		// the act of sumbitting of assignment may be considered private - only graders will see it if specified
		if (empty($CFG->assignment_showrecentsubmissions)) {
			if (!array_key_exists($cm->id, $grader)) {
				$grader[$cm->id] = has_capability('moodle/grade:viewall', get_context_instance(CONTEXT_MODULE, $cm->id));
			}
			if (!$grader[$cm->id]) {
				continue;
			}
		}

		$groupmode = groups_get_activity_groupmode($cm, $course);

		if ($groupmode == SEPARATEGROUPS and !has_capability('moodle/site:accessallgroups', get_context_instance(CONTEXT_MODULE, $cm->id))) {
			if (isguestuser()) {
				// shortcut - guest user does not belong into any group
				continue;
			}

			if (is_null($modinfo->groups)) {
				$modinfo->groups = groups_get_user_groups($course->id); // load all my groups and cache it in modinfo
			}

			// this will be slow - show only users that share group with me in this cm
			if (empty($modinfo->groups[$cm->id])) {
				continue;
			}
			$usersgroups =  groups_get_all_groups($course->id, $cm->userid, $cm->groupingid);
			if (is_array($usersgroups)) {
				$usersgroups = array_keys($usersgroups);
				$interset = array_intersect($usersgroups, $modinfo->groups[$cm->id]);
				if (empty($intersect)) {
					continue;
				}
			}
		}
		$show[] = $submission;
	}

	if (empty($show)) {
		return false;
	}

	print_headline(get_string('newsubmissions', 'assignment').':');

	foreach ($show as $submission) {
		$cm = $modinfo->cms[$submission->cmid];
		$link = $CFG->wwwroot.'/mod/assignment/view.php?id='.$cm->id;
		print_recent_activity_note($submission->timemodified, $submission, $cm->name, $link, false, $viewfullnames);
	}

	return true;
}


/**
 * Returns all assignments since a given time in specified forum.
 */
function assignment_get_recent_mod_activity(&$activities, &$index, $timestart, $courseid, $cmid, $userid=0, $groupid=0)  {

	global $CFG, $COURSE, $USER;

	if ($COURSE->id == $courseid) {
		$course = $COURSE;
	} else {
		$course = get_record('course', 'id', $courseid);
	}

	$modinfo =& get_fast_modinfo($course);

	$cm = $modinfo->cms[$cmid];

	if ($userid) {
		$userselect = "AND u.id = $userid";
	} else {
		$userselect = "";
	}

	if ($groupid) {
		$groupselect = "AND gm.groupid = $groupid";
		$groupjoin   = "JOIN {$CFG->prefix}groups_members gm ON  gm.userid=u.id";
	} else {
		$groupselect = "";
		$groupjoin   = "";
	}

	if (!$submissions = get_records_sql("SELECT asb.id, asb.timemodified, asb.userid,
												u.firstname, u.lastname, u.email, u.picture
										   FROM {$CFG->prefix}assignment_submissions asb
												JOIN {$CFG->prefix}assignment a	  ON a.id = asb.assignment
												JOIN {$CFG->prefix}user u			ON u.id = asb.userid
												$groupjoin
										  WHERE asb.timemodified > $timestart AND a.id = $cm->instance
												$userselect $groupselect
									   ORDER BY asb.timemodified ASC")) {
		 return;
	}

	$groupmode	   = groups_get_activity_groupmode($cm, $course);
	$cm_context	  = get_context_instance(CONTEXT_MODULE, $cm->id);
	$grader		  = has_capability('moodle/grade:viewall', $cm_context);
	$accessallgroups = has_capability('moodle/site:accessallgroups', $cm_context);
	$viewfullnames   = has_capability('moodle/site:viewfullnames', $cm_context);

	if (is_null($modinfo->groups)) {
		$modinfo->groups = groups_get_user_groups($course->id); // load all my groups and cache it in modinfo
	}

	$show = array();

	foreach($submissions as $submission) {
		if ($submission->userid == $USER->id) {
			$show[] = $submission;
			continue;
		}
		// the act of submitting of assignment may be considered private - only graders will see it if specified
		if (empty($CFG->assignment_showrecentsubmissions)) {
			if (!$grader) {
				continue;
			}
		}

		if ($groupmode == SEPARATEGROUPS and !$accessallgroups) {
			if (isguestuser()) {
				// shortcut - guest user does not belong into any group
				continue;
			}

			// this will be slow - show only users that share group with me in this cm
			if (empty($modinfo->groups[$cm->id])) {
				continue;
			}
			$usersgroups = groups_get_all_groups($course->id, $cm->userid, $cm->groupingid);
			if (is_array($usersgroups)) {
				$usersgroups = array_keys($usersgroups);
				$interset = array_intersect($usersgroups, $modinfo->groups[$cm->id]);
				if (empty($intersect)) {
					continue;
				}
			}
		}
		$show[] = $submission;
	}

	if (empty($show)) {
		return;
	}

	if ($grader) {
		require_once($CFG->libdir.'/gradelib.php');
		$userids = array();
		foreach ($show as $id=>$submission) {
			$userids[] = $submission->userid;

		}
		$grades = grade_get_grades($courseid, 'mod', 'assignment', $cm->instance, $userids);
	}

	$aname = format_string($cm->name,true);
	foreach ($show as $submission) {
		$tmpactivity = new object();

		$tmpactivity->type		 = 'assignment';
		$tmpactivity->cmid		 = $cm->id;
		$tmpactivity->name		 = $aname;
		$tmpactivity->sectionnum   = $cm->sectionnum;
		$tmpactivity->timestamp	= $submission->timemodified;

		if ($grader) {
			$tmpactivity->grade = $grades->items[0]->grades[$submission->userid]->str_long_grade;
		}

		$tmpactivity->user->userid   = $submission->userid;
		$tmpactivity->user->fullname = fullname($submission, $viewfullnames);
		$tmpactivity->user->picture  = $submission->picture;

		$activities[$index++] = $tmpactivity;
	}

	return;
}

/**
 * Print recent activity from all assignments in a given course
 *
 * This is used by course/recent.php
 */
function assignment_print_recent_mod_activity($activity, $courseid, $detail, $modnames)  {
	global $CFG;

	echo '<table border="0" cellpadding="3" cellspacing="0" class="assignment-recent">';

	echo "<tr><td class=\"userpicture\" valign=\"top\">";
	print_user_picture($activity->user->userid, $courseid, $activity->user->picture);
	echo "</td><td>";

	if ($detail) {
		$modname = $modnames[$activity->type];
		echo '<div class="title">';
		echo "<img src=\"$CFG->modpixpath/assignment/icon.gif\" ".
			 "class=\"icon\" alt=\"$modname\">";
		echo "<a href=\"$CFG->wwwroot/mod/assignment/view.php?id={$activity->cmid}\">{$activity->name}</a>";
		echo '</div>';
	}

	if (isset($activity->grade)) {
		echo '<div class="grade">';
		echo get_string('grade').': ';
		echo $activity->grade;
		echo '</div>';
	}

	echo '<div class="user">';
	echo "<a href=\"$CFG->wwwroot/user/view.php?id={$activity->user->userid}&amp;course=$courseid\">"
		 ."{$activity->user->fullname}</a>  - ".userdate($activity->timestamp);
	echo '</div>';

	echo "</td></tr></table>";
}

/// GENERIC SQL FUNCTIONS

/**
 * Fetch info from logs
 *
 * @param $log object with properties ->info (the assignment id) and ->userid
 * @return array with assignment name and user firstname and lastname
 */
function assignment_log_info($log) {
	global $CFG;
	return get_record_sql("SELECT a.name, u.firstname, u.lastname
							 FROM {$CFG->prefix}assignment a,
								  {$CFG->prefix}user u
							WHERE a.id = '$log->info'
							  AND u.id = '$log->userid'");
}

/**
 * Return list of marked submissions that have not been mailed out for currently enrolled students
 *
 * @return array
 */
function assignment_get_unmailed_submissions($starttime, $endtime) {

	global $CFG;

	return get_records_sql("SELECT s.*, a.course, a.name
							  FROM {$CFG->prefix}assignment_submissions s,
								   {$CFG->prefix}assignment a
							 WHERE s.mailed = 0
							   AND s.timemarked <= $endtime
							   AND s.timemarked >= $starttime
							   AND s.assignment = a.id");

	/* return get_records_sql("SELECT s.*, a.course, a.name
							  FROM {$CFG->prefix}assignment_submissions s,
								   {$CFG->prefix}assignment a,
								   {$CFG->prefix}user_students us
							 WHERE s.mailed = 0
							   AND s.timemarked <= $endtime
							   AND s.timemarked >= $starttime
							   AND s.assignment = a.id
							   AND s.userid = us.userid
							   AND a.course = us.course");
	*/
}

/**
 * Counts all real assignment submissions by ENROLLED students (not empty ones)
 *
 * There are also assignment type methods count_real_submissions() wich in the default
 * implementation simply call this function.
 * @param $groupid int optional If nonzero then count is restricted to this group
 * @return int The number of submissions
 */
function assignment_count_real_submissions($cm, $groupid=0) {
	global $CFG;

	$context = get_context_instance(CONTEXT_MODULE, $cm->id);

	// this is all the users with this capability set, in this context or higher
	if ($users = get_users_by_capability($context, 'mod/assignment:submit', 'u.id', '', '', '', $groupid, '', false)) {
		$users = array_keys($users);
	}

	// if groupmembersonly used, remove users who are not in any group
	if ($users and !empty($CFG->enablegroupings) and $cm->groupmembersonly) {
		if ($groupingusers = groups_get_grouping_members($cm->groupingid, 'u.id', 'u.id')) {
			$users = array_intersect($users, array_keys($groupingusers));
		}
	}

	if (empty($users)) {
		return 0;
	}

	$userlists = implode(',', $users);

	return count_records_sql("SELECT COUNT('x')
								FROM {$CFG->prefix}assignment_submissions
							   WHERE assignment = $cm->instance AND
									 timemodified > 0 AND
									 userid IN ($userlists)");
}


/**
 * Return all assignment submissions by ENROLLED students (even empty)
 *
 * There are also assignment type methods get_submissions() wich in the default
 * implementation simply call this function.
 * @param $sort string optional field names for the ORDER BY in the sql query
 * @param $dir string optional specifying the sort direction, defaults to DESC
 * @return array The submission objects indexed by id
 */
function assignment_get_all_submissions($assignment, $sort="", $dir="DESC") {
/// Return all assignment submissions by ENROLLED students (even empty)
	global $CFG;

	if ($sort == "lastname" or $sort == "firstname") {
		$sort = "u.$sort $dir";
	} else if (empty($sort)) {
		$sort = "a.timemodified DESC";
	} else {
		$sort = "a.$sort $dir";
	}

	/* not sure this is needed at all since assignmenet already has a course define, so this join?
	$select = "s.course = '$assignment->course' AND";
	if ($assignment->course == SITEID) {
		$select = '';
	}*/

	return get_records_sql("SELECT a.*
							  FROM {$CFG->prefix}assignment_submissions a,
								   {$CFG->prefix}user u
							 WHERE u.id = a.userid
							   AND a.assignment = '$assignment->id'
						  ORDER BY $sort");

	/* return get_records_sql("SELECT a.*
							  FROM {$CFG->prefix}assignment_submissions a,
								   {$CFG->prefix}user_students s,
								   {$CFG->prefix}user u
							 WHERE a.userid = s.userid
							   AND u.id = a.userid
							   AND $select a.assignment = '$assignment->id'
						  ORDER BY $sort");
	*/
}

/**
 * Add a get_coursemodule_info function in case any assignment type wants to add 'extra' information
 * for the course (see resource).
 *
 * Given a course_module object, this function returns any "extra" information that may be needed
 * when printing this activity in a course listing.  See get_array_of_activities() in course/lib.php.
 *
 * @param $coursemodule object The coursemodule object (record).
 * @return object An object on information that the coures will know about (most noticeably, an icon).
 *
 */
function assignment_get_coursemodule_info($coursemodule) {
	global $CFG;

	if (! $assignment = get_record('assignment', 'id', $coursemodule->instance, '', '', '', '', 'id, assignmenttype, name')) {
		return false;
	}

	$libfile = "$CFG->dirroot/mod/assignment/type/$assignment->assignmenttype/assignment.class.php";

	if (file_exists($libfile)) {
		require_once($libfile);
		$assignmentclass = "assignment_$assignment->assignmenttype";
		$ass = new $assignmentclass('staticonly');
		if ($result = $ass->get_coursemodule_info($coursemodule)) {
			return $result;
		} else {
			$info = new object();
			$info->name = $assignment->name;
			return $info;
		}

	} else {
		debugging('Incorrect assignment type: '.$assignment->assignmenttype);
		return false;
	}
}



/// OTHER GENERAL FUNCTIONS FOR ASSIGNMENTS  ///////////////////////////////////////

/**
 * Returns an array of installed assignment types indexed and sorted by name
 *
 * @return array The index is the name of the assignment type, the value its full name from the language strings
 */
function assignment_types() {
	$types = array();
	$names = get_list_of_plugins('mod/assignment/type');
	foreach ($names as $name) {
		$types[$name] = get_string('type'.$name, 'assignment');
	}
	asort($types);
	return $types;
}

/**
 * Executes upgrade scripts for assignment types when necessary
 */
function assignment_upgrade_submodules() {

	global $CFG;

/// Install/upgrade assignment types (it uses, simply, the standard plugin architecture)
	upgrade_plugins('assignment_type', 'mod/assignment/type', "$CFG->wwwroot/$CFG->admin/index.php");

}

function assignment_print_overview($courses, &$htmlarray) {

	global $USER, $CFG;

	if (empty($courses) || !is_array($courses) || count($courses) == 0) {
		return array();
	}

	if (!$assignments = get_all_instances_in_courses('assignment',$courses)) {
		return;
	}

	// Do assignment_base::isopen() here without loading the whole thing for speed
	foreach ($assignments as $key => $assignment) {
		$time = time();
		if ($assignment->timedue) {
			if ($assignment->preventlate) {
				$isopen = ($assignment->timeavailable <= $time && $time <= $assignment->timedue);
			} else {
				$isopen = ($assignment->timeavailable <= $time);
			}
		}
		if (empty($isopen) || empty($assignment->timedue)) {
			unset($assignments[$key]);
		}
	}

	$strduedate = get_string('duedate', 'assignment');
	$strduedateno = get_string('duedateno', 'assignment');
	$strgraded = get_string('graded', 'assignment');
	$strnotgradedyet = get_string('notgradedyet', 'assignment');
	$strnotsubmittedyet = get_string('notsubmittedyet', 'assignment');
	$strsubmitted = get_string('submitted', 'assignment');
	$strassignment = get_string('modulename', 'assignment');
	$strreviewed = get_string('reviewed','assignment');

	foreach ($assignments as $assignment) {
		$str = '<div class="assignment overview"><div class="name">'.$strassignment. ': '.
			   '<a '.($assignment->visible ? '':' class="dimmed"').
			   'title="'.$strassignment.'" href="'.$CFG->wwwroot.
			   '/mod/assignment/view.php?id='.$assignment->coursemodule.'">'.
			   $assignment->name.'</a></div>';
		if ($assignment->timedue) {
			$str .= '<div class="info">'.$strduedate.': '.userdate($assignment->timedue).'</div>';
		} else {
			$str .= '<div class="info">'.$strduedateno.'</div>';
		}
		$context = get_context_instance(CONTEXT_MODULE, $assignment->coursemodule);
		if (has_capability('mod/assignment:grade', $context)) {

			// count how many people can submit
			$submissions = 0; // init
			if ($students = get_users_by_capability($context, 'mod/assignment:submit', '', '', '', '', 0, '', false)) {
				 foreach ($students as $student) {
					if (record_exists_sql("SELECT id FROM {$CFG->prefix}assignment_submissions
										   WHERE assignment = $assignment->id AND
											   userid = $student->id AND
											   teacher = 0 AND
											   timemarked = 0")) {
						$submissions++;
					}
				}
			}

			if ($submissions) {
				$str .= get_string('submissionsnotgraded', 'assignment', $submissions);
			}
		} else {
			$sql = "SELECT *
					  FROM {$CFG->prefix}assignment_submissions
					 WHERE userid = '$USER->id'
					   AND assignment = '{$assignment->id}'";
			if ($submission = get_record_sql($sql)) {
				if ($submission->teacher == 0 && $submission->timemarked == 0) {
					$str .= $strsubmitted . ', ' . $strnotgradedyet;
				} else if ($submission->grade <= 0) {
					$str .= $strsubmitted . ', ' . $strreviewed;
				} else {
					$str .= $strsubmitted . ', ' . $strgraded;
				}
			} else {
				$str .= $strnotsubmittedyet . ' ' . assignment_display_lateness(time(), $assignment->timedue);
			}
		}
		$str .= '</div>';
		if (empty($htmlarray[$assignment->course]['assignment'])) {
			$htmlarray[$assignment->course]['assignment'] = $str;
		} else {
			$htmlarray[$assignment->course]['assignment'] .= $str;
		}
	}
}

function assignment_display_lateness($timesubmitted, $timedue) {
	if (!$timedue) {
		return '';
	}
	$time = $timedue - $timesubmitted;
	if ($time < 0) {
		$timetext = get_string('late', 'assignment', format_time($time));
		return ' (<span class="late">'.$timetext.'</span>)';
	} else {
		$timetext = get_string('early', 'assignment', format_time($time));
		return ' (<span class="early">'.$timetext.'</span>)';
	}
}

function assignment_get_view_actions() {
	return array('view');
}

function assignment_get_post_actions() {
	return array('upload');
}

function assignment_get_types() {
	global $CFG;
	$types = array();

	$type = new object();
	$type->modclass = MOD_CLASS_ACTIVITY;
	$type->type = "assignment_group_start";
	$type->typestr = '--'.get_string('modulenameplural', 'assignment');
	$types[] = $type;

	$standardassignments = array('upload','online','uploadsingle','offline');
	foreach ($standardassignments as $assignmenttype) {
		$type = new object();
		$type->modclass = MOD_CLASS_ACTIVITY;
		$type->type = "assignment&amp;type=$assignmenttype";
		$type->typestr = get_string("type$assignmenttype", 'assignment');
		$types[] = $type;
	}

	/// Drop-in extra assignment types
	$assignmenttypes = get_list_of_plugins('mod/assignment/type');
	foreach ($assignmenttypes as $assignmenttype) {
		if (!empty($CFG->{'assignment_hide_'.$assignmenttype})) {  // Not wanted
			continue;
		}
		if (!in_array($assignmenttype, $standardassignments)) {
			$type = new object();
			$type->modclass = MOD_CLASS_ACTIVITY;
			$type->type = "assignment&amp;type=$assignmenttype";
			$type->typestr = get_string("type$assignmenttype", 'assignment');
			$types[] = $type;
		}
	}

	$type = new object();
	$type->modclass = MOD_CLASS_ACTIVITY;
	$type->type = "assignment_group_end";
	$type->typestr = '--';
	$types[] = $type;

	return $types;
}

/**
 * Removes all grades from gradebook
 * @param int $courseid
 * @param string optional type
 */
function assignment_reset_gradebook($courseid, $type='') {
	global $CFG;

	$type = $type ? "AND a.assignmenttype='$type'" : '';

	$sql = "SELECT a.*, cm.idnumber as cmidnumber, a.course as courseid
			  FROM {$CFG->prefix}assignment a, {$CFG->prefix}course_modules cm, {$CFG->prefix}modules m
			 WHERE m.name='assignment' AND m.id=cm.module AND cm.instance=a.id AND a.course=$courseid $type";

	if ($assignments = get_records_sql($sql)) {
		foreach ($assignments as $assignment) {
			assignment_grade_item_update($assignment, 'reset');
		}
	}
}

/**
 * This function is used by the reset_course_userdata function in moodlelib.
 * This function will remove all posts from the specified assignment
 * and clean up any related data.
 * @param $data the data submitted from the reset course.
 * @return array status array
 */
function assignment_reset_userdata($data) {
	global $CFG;

	$status = array();

	foreach (get_list_of_plugins('mod/assignment/type') as $type) {
		require_once("$CFG->dirroot/mod/assignment/type/$type/assignment.class.php");
		$assignmentclass = "assignment_$type";
		$ass = new $assignmentclass();
		$status = array_merge($status, $ass->reset_userdata($data));
	}

	return $status;
}

/**
 * Implementation of the function for printing the form elements that control
 * whether the course reset functionality affects the assignment.
 * @param $mform form passed by reference
 */
function assignment_reset_course_form_definition(&$mform) {
	$mform->addElement('header', 'assignmentheader', get_string('modulenameplural', 'assignment'));
	$mform->addElement('advcheckbox', 'reset_assignment_submissions', get_string('deleteallsubmissions','assignment'));
}

/**
 * Course reset form defaults.
 */
function assignment_reset_course_form_defaults($course) {
	return array('reset_assignment_submissions'=>1);
}

/**
 * Returns all other caps used in module
 */
function assignment_get_extra_capabilities() {
	return array('moodle/site:accessallgroups', 'moodle/site:viewfullnames');
}

?>
